Controlling Bacterial Biofilms in Cystic Fibrosis Airways

在这个建议中，我们描述了一个新的途径，信号PMN流入和损害的气道，可能发挥的作用，作为一个启动器或辅助因子慢性阻塞性肺疾病（COPD）。具体而言，胶原蛋白的化学或酶促分解释放三肽、PGP和/或在体外对PMN具有趋化性的相关含PGP序列。我们证明，PGP进入气道的引入会导致中性粒细胞的大量涌入，但不是单核细胞。值得注意的是，PGP的PMN趋化活性可能是由于与CXC趋化因子如IL-8的受体结合结构域的显著结构相关性，所述CXC趋化因子含有该胶原序列或接近的类似物。气道长时间暴露于这种肽会导致肺泡扩大和右心室肥大，从而重现COPD的各个方面。此外，使用电喷雾电离-液相色谱-质谱法（ESI-LC-MS/MS），PGP被发现在暴露于雾化LPS的动物的气道中，并显着有助于PMN内流。我们已经将PGP从CXC受体（R）激动剂转化为部分激动剂，最后通过系统地将N和/或C末端的L与P的D异构体交换而成为拮抗剂。（D-P）G（D-P）在体外拮抗PGP以及IL-8趋化活性。我们发现PGP存在于几乎所有COPD患者的支气管肺泡灌洗液（BALF）和/或痰液中，但不存在于对照组或哮喘患者中。此外，来自COPD患者而非对照个体的痰含有从纯化的胶原蛋白离体产生PGP所必需的所有酶机制。总的来说，这些发现使我们假设PGP代表了可能导致疾病的COPD的新生物标志物。作为一个推论，我们认为PGP是COPD的一个有吸引力的治疗靶点。这些假设将通过多学科、多方面的方法进行测试，以开发（D-P）G（D-P）作为一种新的治疗方法，同时抑制嗜酸性炎症的IL-8和PGP途径，因此可能有助于COPD的管理。此外，我们将评估PGP作为COPD的新生物标志物以及（D-P）G（D-P）作为治疗剂的潜在效用的指示剂。

In this proposal, we describe a new pathway signaling PMN influx and damage to the airways that may play a role as an initiator or cofactor for chronic obstructive pulmonary disease (COPD). Specifically, chemical or enzymatic breakdown of collagen releases a tripeptide, PGP, and/or a related PGP-containing sequence that is chemotactic for PMN in vitro. We demonstrate that introduction of PGP into the airways causes a robust influx of PMN, but not monocytes. Remarkably, the PMN chemotactic activity of PGP may be due to a marked structural relatedness to a receptor binding domain of CXC chemokines such as IL-8 which contain this collagen sequence or a close analog. Prolonged airway exposure to this peptide causes alveolar enlargement and right ventricular hypertrophy and thus recapitulates aspects of COPD. Furthermore, using electrospray ionization-liquid chromatography-mass spectrometry (ESI-LC-MS/MS), PGP is found in the airways of animals exposed to aerosolized LPS and markedly contributes to PMN influx. We have converted PGP from a CXC receptor (R) agonist to a partial agonist and finally an antagonist by systematically exchanging L with D isomers of P on the N and/or C termini. (D-P)G(D-P) antagonizes PGP as well as IL-8 chemotactic activity in vitro. We have found that PGP is present in bronchoalveolar lavage fluids (BALF) and/or sputum from virtually all COPD patients but not controls or asthmatics. Furthermore, sputum from COPD patients but not control individuals contains all the enzymatic machinery necessary for the ex vivo generation of PGP from purified collagen. Collectively, these findings lead us to hypothesize that PGP represents a novel biomarker for COPD that may contribute to disease. As a corollary, we theorize that PGP represents an attractive therapeutic target in COPD. These hypotheses will be tested via a multidisciplinary, multifaceted approach to develop (D-P)G(D-P) as a new therapeutic that will simultaneously inhibit both the IL- 8 and PGP pathways of neutrophilic inflammation and, consequently, may be useful in the management of COPD. In addition, we will evaluate PGP as a novel biomarker for COPD as well as a prognosticator of potential utility of (D-P)G(D-P) as a therapeutic agent.